Bung: A traditional practice of potato cultivation in eastern hills of Nepal

Eastern hill region is one of the high potato producing areas of potato in Nepal. There are many traditional potato production systems existing in the region. Among them, 'Bung' and 'Lhose' are very popular systems. There are some under-proven views of naming to this unique cultivation practice. Field observations, key informants' interview, and group discussion were carried out at three sites of Okhaldhunga and Solukhumbu districts in July 2019 to explore the basic information on the bung system. The results of this investigation revealed that the century-old practice utilized marginal sloppy lands of mountains for cultivation of potatoes. Farmers left land fallow for 4-5 years to grow weeds and herbs. Thereafter, they slashed them with a thin layer of soil, stacked them over winter, burned and mixed with the soil making a raised pit. They planted 15-25 potato seed tubers into these pits depending upon the pit size. No additional fertilizer is added to these pits. No intercultural operations are carried out until harvesting. It was explained that the yield of potato from the bung was significantly higher   15-20 kg)  than that of general local practice called lhose system (5-7 kg) from the area equivalent to Bung . Some interventions such as high yielding varieties, easy-to-handle equipment for bung preparation and introduction of fast-growing non-hazardous weeds, etc. were the demands of the farmers to increase profit from the bung system

Balancing polynomials, Fibonacci numbers and some new series for π\pi

We evaluate some types of infinite series with balancing and Lucas-balancing polynomials in closed form. These evaluations will lead to some new curious series for $\pi$ involving Fibonacci and Lucas numbers. Our findings complement those of Castellanos from 1986 and 1989.Comment: 16 pages, 5 table

On some new families of kk-Mersenne and generalized kk-Gaussian Mersenne numbers and their polynomials

In this paper, we define the generalized k-Mersenne numbers and give a formula of generalized Mersenne polynomials and further, we study their properties. Moreover, we define Gaussian Mersenne numbers and obtain some identities like Binet Formula, Cassini's identity, D'Ocagne's Identity, and generating functions. The generalized Gaussian Mersenne numbers are described and their relation with the classical Mersenne numbers are explained. We also introduce a generalization of Gaussian Mersenne polynomials and establish some properties of these polynomials

Growth and yield responses of potato (Solanum tuberosum L.) to biochar

Saabunud / Received 19.06.2020 ; Aktsepteeritud / Accepted 18.09.2020 ; Avaldatud veebis / Published online 18.09.2020 ; Vastutav autor / Corresponding author: Kalika Prasad Upadhyay e-mail: [email protected] response of five types of biochar (Lantana camara, Ipomoea carnea, rice husk, sawdust, no biochar) on growth and yield attributes of potato was evaluated. The experiment was laid out in randomized complete block design with six replications in rainfed areas of two different environments (Jiri in 2018 and Pawati in 2019) of Nepal. The popular early maturing potato variety 'Desiree' was used in the experiment. The spacing was maintained 60 cm between rows and 25 cm between plants in the plot size of 7.2 m2. Seed tubers were planted in the 1st week of February and harvested in the 4th week of May. Recommended fertilizers (100:60:60 kg ha–1 NPK + 20 t ha–1 farmyard manure) and biochars at 2 t ha–1 were applied to the soil. Seed tubers were completely covered with an equal amount of biochar before covering with the soil. The results revealed that the total yield and marketable yield of potato varied with biochars types. The potato tuber yield was found higher and red ants infestation was lower in plots applied with biochars as compared to control plots (without biochars). The use of biochars derived from Lantana camera produced the highest number of tubers (6.1 tubers plant–1), the greatest weight of tubers (286.1 g plant–1) and the least damage of red ants on tubers (4.7%) followed by sawdust (6.0 tubers plant–1, 263.6 g tuber weight plant–1 and 7.8% damaged tubers by red ants). The findings provide new information on the understanding of biochar effect on increased marketable yield of potato in rainfed lands by reducing damage from red ants

Protocol : a method to study the direct reprogramming of lateral root primordia to fertile shoots

Background: Plants have the remarkable property to elaborate entire body plan from any tissue part. The conversion of lateral root primordium (LRP) to shoot is an ideal method for plant propagation and for plant researchers to understand the mechanism underlying trans-differentiation. Until now, however, a robust method that allows the efficient conversion of LRP to shoot is lacking. This has limited our ability to study the dynamic phases of reprogramming at cellular and molecular levels. Results: Here we present an efficient protocol for the direct conversion of LRP to a complete fertile shoot system. This protocol can be readily applied to the various ecotypes of Arabidopsis. We show that, the conversion process is highly responsive to developmental stages of LRP and changes in external environmental stimuli such as temperature. The entire conversion process can be adequately analyzed by histological and imaging techniques. As a demonstration, using a battery of cell fate specific markers, we show that confocal time-lapse imaging can be employed to uncover the early molecular events, intermediate developmental phases and relative abundance of stem cell regulators during the conversion of LRP to shoot. Conclusion: Our method is highly efficient, independent of genotypes tested and suitable to study the reprogramming of LRP to shoot in intact plants as well as in excised roots.Peer reviewe